This invention relates to the art of polysulfide polymers, particularly liquid thiol terminated polysulfide polymers, curing thereof, particularly co-cures with other functionally suitable polymers and to the art of insulated glass windows, particularly the fabrication of sealants therefor.
The use of liquid thiol terminated polysulfide polymers in the formulation of sealants for insulated glass window sandwiches is well known and such sealants are in commercial use. These sealants, because of their polar nature, are somewhat permeable to water vapor. For premium properties with regard to the exclusion of water vapor from the interior of insulated window sandwiches the application of a first sealant layer with a high impermeability to moisture vapor, such as a butyl latex caulk, has been required in commercial practice until now. These highly impermeable caulks or sealants have inherently low physical strength and so the use of a second higher strength sealant, such as the polysulfide based sealants, or a mechanical support means has been required to attain an adequate balance of premium moisture exclusion and structural strength.
The present invention provides a composition which gives excellent structural strength coupled with low moisture vapor permeability.
Applicant is unaware of any art material to the patentability of the invention claimed in this application.